THERE ARE PROBABLY TIMES when you're playing through a solo section and find yourself wanting a different sound than your basic blues scale harmonies. Often a tune will call for a more contemporary approach in the solo, simply because the harmonies lend themselves to it. In this case, it can be very hip to use chords and melodic phrases using fourths.

Playing in fourths will almost force you to play in a different way than you would when using blues scales and other diatonic lines. You will find that your lines will have more large intervals in them, and you will generally play more rhythmically and percussively.

When you're first applying fourths in your soloing, it would be best to start with a solo section that has a one- or two-chord structure. This way you can concentrate on working with the fourths concept, rather than having to worry about playing through a lot of changes. Here is an example of a 32-bar solo section, and the E natural minor scale you might be using to build your solo:

Now build a three-note fourth-chord on each step of the scale. As you can see, the fourth-chord on the 6th includes two non-diatonic notes.

Play these chords with your right hand and play the E pedal under all of them with the left. This way you can hear all the different harmonies and see how they fit the E minor scale. Without the low E, it will sound like the harmonies are floating freely, but when the tonic is played in the bass it will all lock up!

Next, take each chord and break the intervals up into eighth-note exercises, so you can get the feeling of playing fourths as intervals. You will find this technique a little different, and it may require some dedicated practice. The three exercises given below will help you develop accuracy and even rhythm with fourths. Play the chords from the example above in the left hand while you play these phrases in the right.

I'm sure that in playing through these exercises you noticed their rather rigid, regimented sound. This comes about because you're playing nothing but fourths in eighth-notes. I picked this approach deliberately to get your ears acquainted with the special sound of fourths. You should also have felt the difference in swing. Fourths have a more rocking, percussive sound as opposed to the smoothness of diatonic playing.

After playing these melodies, you may ask, "Why not just play pentatonic?" It's true that you could play passages similar to these by starting from a pentatonic scale concept, but the problem is that most players favor the blues scale when they play pentatonic, and it all ends up sounding the same again. The idea here is to stay away from the blues scale, and work toward a sound that's a little more creative and personal.

Learning how to use this approach takes time and lots of playing. The most inspiring thing about the fourths technique is that it's coming from another musical direction and gives you an additional approach for creating variety in your soloing. One of the most important things you can achieve as a keyboardist is to be versatile. This will keep you working.